They’re all different things to be honest, mostly depends which assistant you want to control them all - Apple, Google or Alexa.
My lights are all Hue. My doorbell and indoor cameras are Google/Nest. My heating is Nest and my speakers are all Sonos. My smart plugs are a mix of Wemo and Kasa (TP Link). My ‘proper’ cctv is a different company completely and not available through any assistant, just the app or computer. Same with the alarm but that’s also monitored.
I control everything via Google or using the individual apps. I could control it via Siri but I prefer the Google set up and have a few Google assistants dotted around the house. Had Alexa for a while but prefer Google.